Modelica.Fluid.Dissipation.PressureLoss.StraightPipe

Package for pressure loss calculation of straight pipes

Information

Straight Pipe

Laminar flow

Calculation of pressure loss in a straight pipe for laminar flow regime of single-phase fluid flow only. See more information.

Turbulent flow

Calculation of pressure loss in a straight pipe for turbulent flow regime of single-phase fluid flow only considering surface roughness. See more information.

Overall flow

Calculation of pressure loss in a straight pipe for laminar or turbulent flow regime of single-phase fluid flow only considering surface roughness. See more information.

Two phase overall flow

Calculation of pressure loss for two phase flow in a horizontal or vertical straight pipe for an overall flow regime considering frictional, momentum and geodetic pressure loss. See more information.

Extends from Modelica.Icons.VariantsPackage (Icon for package containing variants).

Package Content

Name Description

dp_laminar_DP Pressure loss of straight pipe | calculate pressure loss| laminar flow regime (Hagen-Poiseuille)

dp_laminar_MFLOW Pressure loss of straight pipe | calculate mass flow rate | laminar flow regime (Hagen-Poiseuille)

dp_laminar_IN_con Input record for function dp_laminar_DP and dp_laminar_MFLOW

dp_laminar_IN_var Input record for function dp_laminar_DP and dp_laminar_MFLOW

dp_overall_DP Pressure loss of straight pipe | calculate pressure loss | overall flow regime | surface roughness

dp_overall_MFLOW Pressure loss of straight pipe | calculate mass flow rate | overall flow regime | surface roughness

dp_overall_IN_con Input record for function dp_overall_DP and dp_overall_MFLOW

dp_overall_IN_var Input record for function dp_overall_DP and dp_overall_MFLOW

dp_turbulent_DP Pressure loss of straight pipe | calculate pressure loss | turbulent flow regime | surface roughness

dp_turbulent_MFLOW Pressure loss of straight pipe | calculate mass flow rate | turbulent flow regime | surface roughness

dp_turbulent_IN_con Input record for function dp_turbulent_DP and dp_turbulent_MFLOW

dp_turbulent_IN_var Input record for function dp_turbulent_DP and dp_turbulent_MFLOW

dp_twoPhaseOverall_DP Pressure loss of straight pipe for two phase flow | calculate (frictional, momentum, geodetic) pressure loss

dp_twoPhaseOverall_IN_con Input record for function dp_twoPhaseOverall_DP

dp_twoPhaseOverall_IN_var Input record for function dp_twoPhaseOverall_DP

Name	Description
dp_laminar_DP	Pressure loss of straight pipe \| calculate pressure loss\| laminar flow regime (Hagen-Poiseuille)
dp_laminar_MFLOW	Pressure loss of straight pipe \| calculate mass flow rate \| laminar flow regime (Hagen-Poiseuille)
dp_laminar_IN_con	Input record for function dp_laminar_DP and dp_laminar_MFLOW
dp_laminar_IN_var	Input record for function dp_laminar_DP and dp_laminar_MFLOW
dp_overall_DP	Pressure loss of straight pipe \| calculate pressure loss \| overall flow regime \| surface roughness
dp_overall_MFLOW	Pressure loss of straight pipe \| calculate mass flow rate \| overall flow regime \| surface roughness
dp_overall_IN_con	Input record for function dp_overall_DP and dp_overall_MFLOW
dp_overall_IN_var	Input record for function dp_overall_DP and dp_overall_MFLOW
dp_turbulent_DP	Pressure loss of straight pipe \| calculate pressure loss \| turbulent flow regime \| surface roughness
dp_turbulent_MFLOW	Pressure loss of straight pipe \| calculate mass flow rate \| turbulent flow regime \| surface roughness
dp_turbulent_IN_con	Input record for function dp_turbulent_DP and dp_turbulent_MFLOW
dp_turbulent_IN_var	Input record for function dp_turbulent_DP and dp_turbulent_MFLOW
dp_twoPhaseOverall_DP	Pressure loss of straight pipe for two phase flow \| calculate (frictional, momentum, geodetic) pressure loss
dp_twoPhaseOverall_IN_con	Input record for function dp_twoPhaseOverall_DP
dp_twoPhaseOverall_IN_var	Input record for function dp_twoPhaseOverall_DP

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_DP

Pressure loss of straight pipe | calculate pressure loss| laminar flow regime (Hagen-Poiseuille)

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_DP

Information

Calculation of pressure loss in a straight pipe for laminar flow regime of an incompressible and single-phase fluid flow only.

Generally this function is numerically best used for the incompressible case , where the mass flow rate (m_flow) is known (as state variable) in the used model and the corresponding pressure loss (DP) has to be calculated. On the other hand the function dp_laminar_MFLOW is numerically best used for the compressible case if the pressure loss (dp) is known (out of pressures as state variable) and the mass flow rate (M_FLOW) has to be calculated. See more information.

Extends from Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d (Geometry figure for straight pipe).

Inputs

Type Name Default Description

Constant inputs

dp_laminar_IN_con IN_con Input record for function dp_laminar_DP

Variable inputs

dp_laminar_IN_var IN_var Input record for function dp_laminar_DP

Input

MassFlowRate m_flow Mass flow rate [kg/s]

Type	Name	Description
Constant inputs
dp_laminar_IN_con	IN_con	Input record for function dp_laminar_DP
Variable inputs
dp_laminar_IN_var	IN_var	Input record for function dp_laminar_DP
Input
MassFlowRate	m_flow	Mass flow rate [kg/s]

Outputs

Type Name Description

Pressure DP Output for function dp_laminar_DP [Pa]

Type	Name	Description
Pressure	DP	Output for function dp_laminar_DP [Pa]

Modelica definition

function dp_laminar_DP 
  "Pressure loss of straight pipe | calculate pressure loss| laminar flow regime (Hagen-Poiseuille)"
  //SOURCE_1: Idelchik, I.E.: HANDBOOK OF HYDRAULIC RESISTANCE, 3rd edition, 2006.

  import FD = Modelica.Fluid.Dissipation.PressureLoss.StraightPipe;

  //icon
  extends Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d;

  //input records
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_IN_con
    IN_con "Input record for function dp_laminar_DP";
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_IN_var
    IN_var "Input record for function dp_laminar_DP";
  input SI.MassFlowRate m_flow "Mass flow rate";

  //output variables
  output SI.Pressure DP "Output for function dp_laminar_DP";

protected 
  Real MIN=Modelica.Constants.eps;

  SI.Diameter d_hyd=IN_con.d_hyd "Hydraulic diameter";
  SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Circular cross sectional area";

  SI.Velocity velocity=m_flow/max(MIN, IN_var.rho*A_cross) "Mean velocity";

  //Documentation

algorithm 
  DP := 32*IN_var.eta*velocity*IN_con.L/d_hyd^2;
end dp_laminar_DP;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_MFLOW

Pressure loss of straight pipe | calculate mass flow rate | laminar flow regime (Hagen-Poiseuille)

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_MFLOW

Information

Calculation of pressure loss in a straight pipe for laminar flow regime of an incompressible and single-phase fluid flow only.

Generally this function is numerically best used for the compressible case , where the pressure loss (dp) is known (out of pressures as state variable) in the used model and the corresponding mass flow rate (M_FLOW) has to be calculated. On the other hand the function dp_laminar_DP is numerically best used for the incompressible case if the mass flow rate (m_flow) is known (as state variable) and the pressure loss (DP) has to be calculated. See more information.

Extends from Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d (Geometry figure for straight pipe).

Inputs

Type Name Default Description

Constant inputs

dp_laminar_IN_con IN_con Input record for function dp_laminar_MFLOW

Variable inputs

dp_laminar_IN_var IN_var Input record for function dp_laminar_MFLOW

Input

Pressure dp Pressure loss [Pa]

Type	Name	Description
Constant inputs
dp_laminar_IN_con	IN_con	Input record for function dp_laminar_MFLOW
Variable inputs
dp_laminar_IN_var	IN_var	Input record for function dp_laminar_MFLOW
Input
Pressure	dp	Pressure loss [Pa]

Outputs

Type Name Description

MassFlowRate M_FLOW Output for function dp_laminar_MFLOW [kg/s]

Type	Name	Description
MassFlowRate	M_FLOW	Output for function dp_laminar_MFLOW [kg/s]

Modelica definition

function dp_laminar_MFLOW 
  "Pressure loss of straight pipe | calculate mass flow rate | laminar flow regime (Hagen-Poiseuille)"
  //SOURCE_1: Idelchik, I.E.: HANDBOOK OF HYDRAULIC RESISTANCE, 3rd edition, 2006.

  import FD = Modelica.Fluid.Dissipation.PressureLoss.StraightPipe;

  //icon
  extends Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d;

  //input records
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_IN_con
    IN_con "Input record for function dp_laminar_MFLOW";
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_IN_var
    IN_var "Input record for function dp_laminar_MFLOW";
  input SI.Pressure dp "Pressure loss";

  //output variables
  output SI.MassFlowRate M_FLOW "Output for function dp_laminar_MFLOW";

protected 
  Real MIN=Modelica.Constants.eps;

  SI.Diameter d_hyd=max(MIN, IN_con.d_hyd) "Hydraulic diameter";
  SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Circular cross sectional area";

  //Documentation

algorithm 
  M_FLOW := IN_var.rho*A_cross*(dp*d_hyd^2/(32*IN_var.eta*IN_con.L));
end dp_laminar_MFLOW;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_IN_con

Input record for function dp_laminar_DP and dp_laminar_MFLOW

Information

This record is used as input record for the pressure loss function dp_laminar_DP and dp_laminar_MFLOW.

Extends from Utilities.Records.PressureLoss.StraightPipe (Input for straight pipe).

Parameters

Type Name Default Description

Straight pipe

Diameter d_hyd 0.1 Hydraulic diameter [m]

Length L 1 Length [m]

Type	Name	Default	Description
Straight pipe
Diameter	d_hyd	0.1	Hydraulic diameter [m]
Length	L	1	Length [m]

Modelica definition

record dp_laminar_IN_con 
  "Input record for function dp_laminar_DP and dp_laminar_MFLOW"
  extends Utilities.Records.PressureLoss.StraightPipe;


end dp_laminar_IN_con;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_laminar_IN_var

Input record for function dp_laminar_DP and dp_laminar_MFLOW

Information

This record is used as input record for the pressure loss function dp_laminar_DP and dp_laminar_MFLOW.

Extends from Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_var (Input record for function dp_overall_DP and dp_overall_MFLOW).

Parameters

Type Name Default Description

Fluid properties

DynamicViscosity eta Dynamic viscosity of fluid [Pa.s]

Density rho Density of fluid [kg/m3]

Type	Name	Description
Fluid properties
DynamicViscosity	eta	Dynamic viscosity of fluid [Pa.s]
Density	rho	Density of fluid [kg/m3]

Modelica definition

record dp_laminar_IN_var 
  "Input record for function dp_laminar_DP and dp_laminar_MFLOW"

  extends Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_var;


end dp_laminar_IN_var;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_DP

Pressure loss of straight pipe | calculate pressure loss | overall flow regime | surface roughness

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_DP

Information

Calculation of pressure loss in a straight pipe for overall flow regime of an incompressible and single-phase fluid flow only considering surface roughness.

Generally this function is numerically best used for the incompressible case , where the mass flow rate (m_flow) is known (as state variable) in the used model and the corresponding pressure loss (DP) has to be calculated. On the other hand the function dp_overall_MFLOW is numerically best used for the compressible case if the pressure loss (dp) is known (out of pressures as state variable) and the mass flow rate (M_FLOW) has to be calculated. See more information.

Extends from Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d (Geometry figure for straight pipe).

Inputs

Type Name Default Description

Constant inputs

dp_overall_IN_con IN_con Input record for function dp_overall_DP

Variable inputs

dp_overall_IN_var IN_var Input record for function dp_overall_DP

Input

MassFlowRate m_flow Mass flow rate [kg/s]

Type	Name	Description
Constant inputs
dp_overall_IN_con	IN_con	Input record for function dp_overall_DP
Variable inputs
dp_overall_IN_var	IN_var	Input record for function dp_overall_DP
Input
MassFlowRate	m_flow	Mass flow rate [kg/s]

Outputs

Type Name Description

Pressure DP Output for function dp_overall_DP [Pa]

Type	Name	Description
Pressure	DP	Output for function dp_overall_DP [Pa]

Modelica definition

function dp_overall_DP 
  "Pressure loss of straight pipe | calculate pressure loss | overall flow regime | surface roughness"
  import FD = Modelica.Fluid.Dissipation.PressureLoss.StraightPipe;
  import SMOOTH = Modelica.Fluid.Dissipation.Utilities.Functions.General.Stepsmoother;

  //icon
  extends Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d;

  //input records
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_con
    IN_con "Input record for function dp_overall_DP";
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_var
    IN_var "Input record for function dp_overall_DP";
  input SI.MassFlowRate m_flow "Mass flow rate";

  //output variables
  output SI.Pressure DP "Output for function dp_overall_DP";

protected 
  Real MIN=Modelica.Constants.eps;

  SI.Diameter d_hyd=max(MIN, IN_con.d_hyd) "Hydraulic diameter";
  SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Circular cross sectional area";
  Real k=max(MIN, abs(IN_con.K)/IN_con.d_hyd) "Relative roughness";
  SI.Length perimeter=PI*IN_con.d_hyd "Perimeter";

  //SOURCE_1: p.81, fig. 2-3, sec 21-22: definition of flow regime boundaries
  SI.ReynoldsNumber Re_lam_min=1e3 "Minimum Reynolds number for laminar regime";
  SI.ReynoldsNumber Re_lam_max=2090*(1/max(0.007, k))^0.0635 
    "Maximum Reynolds number for laminar regime";
  SI.ReynoldsNumber Re_lam_leave=min(Re_lam_max, max(Re_lam_min, 754*
      Modelica.Math.exp(if k <= 0.007 then 0.0065/0.007 else 0.0065/k))) 
    "Start of transition regime for increasing Reynolds number (leaving laminar regime)";

  SI.ReynoldsNumber Re=
      Modelica.Fluid.Dissipation.Utilities.Functions.General.ReynoldsNumber(
      A_cross,
      perimeter,
      IN_var.rho,
      IN_var.eta,
      m_flow);

  //Documentation

algorithm 
  DP := SMOOTH(
          Re_lam_min,
          Re_lam_max,
          Re)*Dissipation.PressureLoss.StraightPipe.dp_laminar_DP(
          IN_con,
          IN_var,
          m_flow) + SMOOTH(
          Re_lam_max,
          Re_lam_min,
          Re)*Dissipation.PressureLoss.StraightPipe.dp_turbulent_DP(
          IN_con,
          IN_var,
          m_flow);
end dp_overall_DP;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_MFLOW

Pressure loss of straight pipe | calculate mass flow rate | overall flow regime | surface roughness

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_MFLOW

Information

Calculation of pressure loss in a straight pipe for overall flow regime of an incompressible and single-phase fluid flow only considering surface roughness.

Generally this function is numerically best used for the compressible case , where the pressure loss (dp) is known (out of pressures as state variable) in the used model and the corresponding mass flow rate (M_FLOW) has to be calculated. On the other hand the function dp_overall_DP is numerically best used for the incompressible case if the mass flow rate (m_flow) is known (as state variable) and the pressure loss (DP) has to be calculated. See more information.

Extends from Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d (Geometry figure for straight pipe).

Inputs

Type Name Default Description

Constant inputs

dp_overall_IN_con IN_con Input record for function dp_overall_MFLOW

Variable inputs

dp_overall_IN_var IN_var Input record for function dp_overall_MFLOW

Input

Pressure dp Pressure loss [Pa]

Type	Name	Description
Constant inputs
dp_overall_IN_con	IN_con	Input record for function dp_overall_MFLOW
Variable inputs
dp_overall_IN_var	IN_var	Input record for function dp_overall_MFLOW
Input
Pressure	dp	Pressure loss [Pa]

Outputs

Type Name Description

MassFlowRate M_FLOW Output of function dp_overall_MFLOW [kg/s]

Type	Name	Description
MassFlowRate	M_FLOW	Output of function dp_overall_MFLOW [kg/s]

Modelica definition

function dp_overall_MFLOW 
  "Pressure loss of straight pipe | calculate mass flow rate | overall flow regime | surface roughness"
  import FD = Modelica.Fluid.Dissipation.PressureLoss.StraightPipe;
  import SMOOTH = Modelica.Fluid.Dissipation.Utilities.Functions.General.Stepsmoother;

  //icon
  extends Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d;

  //input records
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_con
    IN_con "Input record for function dp_overall_MFLOW";
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_var
    IN_var "Input record for function dp_overall_MFLOW";
  input SI.Pressure dp "Pressure loss";

  //output variables
  output SI.MassFlowRate M_FLOW "Output of function dp_overall_MFLOW";

protected 
  Real MIN=Modelica.Constants.eps;

  SI.Diameter d_hyd=max(MIN, IN_con.d_hyd) "Hydraulic diameter";
  SI.Area A_cross=max(MIN, PI*IN_con.d_hyd^2/4) "Circular cross sectional area";
  Real k=max(MIN, abs(IN_con.K)/IN_con.d_hyd) "Relative roughness";

  //SOURCE_1: p.81, fig. 2-3, sec 21-22: definition of flow regime boundaries
  SI.ReynoldsNumber Re_lam_min=1e3 "Minimum Reynolds number for laminar regime";
  SI.ReynoldsNumber Re_lam_max=2090*(1/max(0.007, k))^0.0635 
    "Maximum Reynolds number for laminar regime";
  SI.ReynoldsNumber Re_turb_min=4e3 
    "Minimum Reynolds number for turbulent regime";

  SI.ReynoldsNumber Re_lam_leave=min(Re_lam_max, max(Re_lam_min, 754*
      Modelica.Math.exp(if k <= 0.007 then 0.0065/0.007 else 0.0065/k))) 
    "Start of transition regime for increasing Reynolds number (leaving laminar regime)";

  //determining darcy friction factor out of pressure loss calulation for straight pipe:
  //dp = lambda_FRI*L/d_hyd*(rho/2)*velocity^2 and assuming lambda_FRI == lambda_FRI_calc/Re^2
  TYP.DarcyFrictionFactor lambda_FRI_calc=2*abs(dp)*d_hyd^3*IN_var.rho/(IN_con.L
      *IN_var.eta^2) "Adapted Darcy friction factor";

  //SOURCE_3: p.Lab 1, eq. 5: determine Re assuming laminar regime (Blasius)
  SI.ReynoldsNumber Re_lam=lambda_FRI_calc/64 
    "Reynolds number assuming laminar regime";

  //SOURCE_3: p.Lab 2, eq. 10: determine Re assuming turbulent regime (Colebrook-White)
  SI.ReynoldsNumber Re_turb=if IN_con.roughness == 1 then (max(MIN,
      lambda_FRI_calc)/0.3164)^(1/1.75) else -2*sqrt(max(lambda_FRI_calc, MIN))
      *Modelica.Math.log10(2.51/sqrt(max(lambda_FRI_calc, MIN)) + k/3.7) 
    "Reynolds number assuming turbulent regime";

  //determine actual flow regime
  SI.ReynoldsNumber Re_check=if Re_lam < Re_lam_leave then Re_lam else Re_turb;
  //determine Re for transition regime
  SI.ReynoldsNumber Re_trans=if Re_lam >= Re_lam_leave then 
      Modelica.Fluid.Dissipation.Utilities.Functions.General.CubicInterpolation_DP(
      Re_check,
      Re_lam_leave,
      Re_turb_min,
      k,
      lambda_FRI_calc) else 0;
  //determine actual Re
  SI.ReynoldsNumber Re=if Re_lam < Re_lam_leave then Re_lam else if Re_turb >
      Re_turb_min then Re_turb else Re_trans;

  //Documentation

algorithm 
  M_FLOW := SMOOTH(
          Re_lam_min,
          Re_turb,
          Re)*Dissipation.PressureLoss.StraightPipe.dp_laminar_MFLOW(
          IN_con,
          IN_var,
          dp) + SMOOTH(
          Re_turb,
          Re_lam_min,
          Re)*Dissipation.PressureLoss.StraightPipe.dp_turbulent_MFLOW(
          IN_con,
          IN_var,
          dp);
end dp_overall_MFLOW;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_con

Input record for function dp_overall_DP and dp_overall_MFLOW

Information

This record is used as input record for the pressure loss function dp_overall_DP and dp_overall_MFLOW.

Extends from dp_turbulent_IN_con (Input record for function dp_turbulent_DP and dp_turbulent_MFLOW).

Parameters

Type Name Default Description

Straight pipe

Roughness roughness Dissipation.Utilities.Types.... Choice of considering surface roughness

Diameter d_hyd 0.1 Hydraulic diameter [m]

Length L 1 Length [m]

Length K 0 Roughness (average height of surface asperities) [m]

Type	Name	Default	Description
Straight pipe
Roughness	roughness	Dissipation.Utilities.Types....	Choice of considering surface roughness
Diameter	d_hyd	0.1	Hydraulic diameter [m]
Length	L	1	Length [m]
Length	K	0	Roughness (average height of surface asperities) [m]

Modelica definition

record dp_overall_IN_con 
  "Input record for function dp_overall_DP and dp_overall_MFLOW"

  //straight pipe variables
  extends dp_turbulent_IN_con;


end dp_overall_IN_con;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_var

Input record for function dp_overall_DP and dp_overall_MFLOW

Information

This record is used as input record for the pressure loss function dp_overall_DP and dp_overall_MFLOW.

Extends from Modelica.Fluid.Dissipation.Utilities.Records.General.PressureLoss (Base record for fluid properties for pressure loss).

Parameters

Type Name Default Description

Fluid properties

DynamicViscosity eta Dynamic viscosity of fluid [Pa.s]

Density rho Density of fluid [kg/m3]

Type	Name	Description
Fluid properties
DynamicViscosity	eta	Dynamic viscosity of fluid [Pa.s]
Density	rho	Density of fluid [kg/m3]

Modelica definition

record dp_overall_IN_var 
  "Input record for function dp_overall_DP and dp_overall_MFLOW"

  //fluid property variables
  extends Modelica.Fluid.Dissipation.Utilities.Records.General.PressureLoss;


end dp_overall_IN_var;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_DP

Pressure loss of straight pipe | calculate pressure loss | turbulent flow regime | surface roughness

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_DP

Information

Calculation of pressure loss in a straight pipe for turbulent flow regime of an incompressible and single-phase fluid flow only considering surface roughness.

Generally this function is numerically best used for the incompressible case , where the mass flow rate (m_flow) is known (as state variable) in the used model and the corresponding pressure loss (DP) has to be calculated. On the other hand the function dp_turbulent_MFLOW is numerically best used for the compressible case if the pressure loss (dp) is known (out of pressures as state variable) and the mass flow rate (M_FLOW) has to be calculated. See more information.

Extends from Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d (Geometry figure for straight pipe).

Inputs

Type Name Default Description

Constant inputs

dp_turbulent_IN_con IN_con Input record for function dp_turbulent_DP

Variable inputs

dp_turbulent_IN_var IN_var Input record for function dp_turbulent_DP

Input

MassFlowRate m_flow Mass flow rate [kg/s]

Type	Name	Description
Constant inputs
dp_turbulent_IN_con	IN_con	Input record for function dp_turbulent_DP
Variable inputs
dp_turbulent_IN_var	IN_var	Input record for function dp_turbulent_DP
Input
MassFlowRate	m_flow	Mass flow rate [kg/s]

Outputs

Type Name Description

Pressure DP Output for function dp_turbulent_DP [Pa]

Type	Name	Description
Pressure	DP	Output for function dp_turbulent_DP [Pa]

Modelica definition

function dp_turbulent_DP 
  "Pressure loss of straight pipe | calculate pressure loss | turbulent flow regime | surface roughness"

  //SOURCE_1: Idelchik, I.E.: HANDBOOK OF HYDRAULIC RESISTANCE, 3rd edition, 2006.
  //SOURCE_2: Miller, D.S.: INTERNAL FLOW SYSTEMS, 2nd edition, 1984.
  //SOURCE_3: VDI-Waermeatlas, 9th edition, Springer-Verlag, 2002.
  import FD = Modelica.Fluid.Dissipation.PressureLoss.StraightPipe;

  //icon
  extends Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d;

  //input records
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_IN_con
    IN_con "Input record for function dp_turbulent_DP";
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_IN_var
    IN_var "Input record for function dp_turbulent_DP";
  input SI.MassFlowRate m_flow "Mass flow rate";

  //output variables
  output SI.Pressure DP "Output for function dp_turbulent_DP";

protected 
  type TYP1 = Modelica.Fluid.Dissipation.Utilities.Types.Roughness;

  Real MIN=Modelica.Constants.eps;

  SI.ReynoldsNumber Re_min=1;
  SI.Velocity v_min=Re_min*IN_var.eta/(IN_var.rho*IN_con.d_hyd);

  SI.Diameter d_hyd=IN_con.d_hyd "Hydraulic diameter";
  SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Circular cross sectional area";
  Real k=max(MIN, abs(IN_con.K)/IN_con.d_hyd) "Relative roughness";

  //SOURCE_1: p.81, fig. 2-3, sec 21-22: definition of flow regime boundaries
  SI.ReynoldsNumber Re_lam_min=1e3 "Minimum Reynolds number for laminar regime";
  SI.ReynoldsNumber Re_lam_max=2090*(1/max(0.007, k))^0.0635 
    "Maximum Reynolds number for laminar regime";
  SI.ReynoldsNumber Re_turb_min=4e3 
    "Minimum Reynolds number for turbulent regime";

  SI.ReynoldsNumber Re_lam_leave=min(Re_lam_max, max(Re_lam_min, 754*
      Modelica.Math.exp(if k <= 0.007 then 0.0065/0.007 else 0.0065/k))) 
    "Start of transition regime for increasing Reynolds number (leaving laminar regime)";

  SI.Velocity velocity=m_flow/(IN_var.rho*A_cross) "Mean velocity";
  SI.ReynoldsNumber Re=max(Re_min, IN_var.rho*abs(velocity)*d_hyd/IN_var.eta);

  //SOURCE_2: p.191, eq. 8.4: determining darcy friction factor
  //assuming lambda_FRI == lambda_FRI_calc/Re^2
  TYP.DarcyFrictionFactor lambda_FRI_smooth=0.3164*Re^(1.75) 
    "Darcy friction factor neglecting surface roughness (Blasius)";
  //here with lambda_FRI_rough == lambda_FRI*Re^2
  TYP.DarcyFrictionFactor lambda_FRI_rough=0.25*(max(Re, Re_lam_leave)/
      Modelica.Math.log10(k/3.7 + 5.74/max(Re, Re_lam_leave)^0.9))^2 
    "Darcy friction factor considering surface roughness";
  TYP.DarcyFrictionFactor lambda_FRI=if IN_con.roughness == TYP1.Neglected then 
            lambda_FRI_smooth else lambda_FRI_rough "Darcy friction factor";
  TYP.DarcyFrictionFactor lambda_FRI_calc=if Re < Re_lam_leave then 64/Re else 
      if Re > Re_turb_min then lambda_FRI/Re^2 else 
      Modelica.Fluid.Dissipation.Utilities.Functions.General.CubicInterpolation_MFLOW(
      Re,
      Re_lam_leave,
      Re_turb_min,
      k)/Re^2 "Darcy friction factor";

  TYP.PressureLossCoefficient zeta_TOT=lambda_FRI_calc*IN_con.L/d_hyd 
    "Pressure loss coefficient";

  //Documentation

algorithm 
  DP := zeta_TOT*(IN_var.rho/2)*
    Modelica.Fluid.Dissipation.Utilities.Functions.General.SmoothPower(
          velocity,
          v_min,
          2);
end dp_turbulent_DP;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_MFLOW

Pressure loss of straight pipe | calculate mass flow rate | turbulent flow regime | surface roughness

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_MFLOW

Information

Calculation of pressure loss in a straight pipe for turbulent flow regime of an incompressible and single-phase fluid flow only considering surface roughness.

Generally this function is numerically best used for the compressible case if the pressure loss (dp) is known (out of pressures as state variable) and the mass flow rate (M_FLOW) has to be calculated. On the other hand the function dp_turbulent_DP is numerically best used for the incompressible case , where the mass flow rate (m_flow) is known (as state variable) in the used model and the corresponding pressure loss (DP) has to be calculated. See more information.

Extends from Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d (Geometry figure for straight pipe).

Inputs

Type Name Default Description

Constant inputs

dp_turbulent_IN_con IN_con Input record for function dp_turbulent_MFLOW

Variable inputs

dp_turbulent_IN_var IN_var Input record for function dp_turbulent_MFLOW

Input

Pressure dp Pressure loss [Pa]

Type	Name	Description
Constant inputs
dp_turbulent_IN_con	IN_con	Input record for function dp_turbulent_MFLOW
Variable inputs
dp_turbulent_IN_var	IN_var	Input record for function dp_turbulent_MFLOW
Input
Pressure	dp	Pressure loss [Pa]

Outputs

Type Name Description

MassFlowRate M_FLOW Mass flow rate [kg/s]

Type	Name	Description
MassFlowRate	M_FLOW	Mass flow rate [kg/s]

Modelica definition

function dp_turbulent_MFLOW 
  "Pressure loss of straight pipe | calculate mass flow rate | turbulent flow regime | surface roughness"
  //SOURCE_1: Idelchik, I.E.: HANDBOOK OF HYDRAULIC RESISTANCE, 3rd edition, 2006.
  //SOURCE_2: Miller, D.S.: INTERNAL FLOW SYSTEMS, 2nd edition, 1984.
  //SOURCE_3: VDI-Waermeatlas, 9th edition, Springer-Verlag, 2002.

  import FD = Modelica.Fluid.Dissipation.PressureLoss.StraightPipe;

  //icon
  extends Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d;
  //input records
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_IN_con
    IN_con "Input record for function dp_turbulent_MFLOW";
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_IN_var
    IN_var "Input record for function dp_turbulent_MFLOW";
  input SI.Pressure dp "Pressure loss";

  //output variables
  output SI.MassFlowRate M_FLOW "Mass flow rate";

protected 
  type TYP1 = Modelica.Fluid.Dissipation.Utilities.Types.Roughness;

  Real MIN=Modelica.Constants.eps;
  SI.ReynoldsNumber Re_min=1;

  SI.Diameter d_hyd=max(MIN, IN_con.d_hyd) "Hydraulic diameter";
  SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Circular cross sectional area";
  Real k=max(MIN, abs(IN_con.K)/IN_con.d_hyd) "Relative roughness";

  //SOURCE_1: p.81, fig. 2-3, sec 21-22: definition of flow regime boundaries
  SI.ReynoldsNumber Re_lam_min=1e3 "Minimum Reynolds number for laminar regime";
  SI.ReynoldsNumber Re_lam_max=2090*(1/max(0.007, k))^0.0635 
    "Maximum Reynolds number for laminar regime";
  SI.ReynoldsNumber Re_turb_min=4e3 
    "Minimum Reynolds number for turbulent regime";

  SI.ReynoldsNumber Re_lam_leave=min(Re_lam_max, max(Re_lam_min, 754*
      Modelica.Math.exp(if k <= 0.007 then 0.0065/0.007 else 0.0065/k))) 
    "Start of transition regime for increasing Reynolds number (leaving laminar regime)";

  //determining darcy friction factor out of pressure loss calulation for straight pipe:
  //dp = lambda_FRI*L/d_hyd*(rho/2)*velocity^2 and assuming lambda_FRI == lambda_FRI_calc/Re^2
  TYP.DarcyFrictionFactor lambda_FRI_calc=2*abs(dp)*d_hyd^3*IN_var.rho/(IN_con.L
      *IN_var.eta^2) "Adapted Darcy friction factor";

  //SOURCE_3: p.Lab 1, eq. 5: determine Re assuming laminar regime (Hagen-Poiseuille)
  SI.ReynoldsNumber Re_lam=lambda_FRI_calc/64 
    "Reynolds number assuming laminar regime";

  //SOURCE_3: p.Lab 2, eq. 10: determine Re assuming turbulent regime (Colebrook-White)
  SI.ReynoldsNumber Re_turb=if IN_con.roughness == TYP1.Neglected then (max(MIN,
      lambda_FRI_calc)/0.3164)^(1/1.75) else -2*sqrt(max(lambda_FRI_calc, MIN))
      *Modelica.Math.log10(2.51/sqrt(max(lambda_FRI_calc, MIN)) + k/3.7) 
    "Reynolds number assuming turbulent regime";

  //determine actual flow regime
  SI.ReynoldsNumber Re_check=if Re_lam < Re_lam_leave then Re_lam else Re_turb;
  //determine Re for transition regime
  SI.ReynoldsNumber Re_trans=if Re_lam >= Re_lam_leave then 
      Modelica.Fluid.Dissipation.Utilities.Functions.General.CubicInterpolation_DP(
      Re_check,
      Re_lam_leave,
      Re_turb_min,
      k,
      lambda_FRI_calc) else 0;
  //determine actual Re
  SI.ReynoldsNumber Re=if Re_lam < Re_lam_leave then Re_lam else if Re_turb >
      Re_turb_min then Re_turb else Re_trans;

  //determine velocity
  SI.Velocity velocity=(if dp >= 0 then Re else -Re)*IN_var.eta/(IN_var.rho*
      d_hyd) "Mean velocity";

  //Documentation

algorithm 
  M_FLOW := IN_var.rho*A_cross*velocity;
end dp_turbulent_MFLOW;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_IN_con

Input record for function dp_turbulent_DP and dp_turbulent_MFLOW

Information

This record is used as input record for the pressure loss function dp_turbulent_DP and dp_turbulent_MFLOW.

Extends from Utilities.Records.PressureLoss.StraightPipe (Input for straight pipe).

Parameters

Type	Name	Default	Description
Straight pipe
Roughness	roughness	Dissipation.Utilities.Types....	Choice of considering surface roughness
Diameter	d_hyd	0.1	Hydraulic diameter [m]
Length	L	1	Length [m]
Length	K	0	Roughness (average height of surface asperities) [m]

Modelica definition

record dp_turbulent_IN_con 
  "Input record for function dp_turbulent_DP and dp_turbulent_MFLOW"

  Modelica.Fluid.Dissipation.Utilities.Types.Roughness roughness=Dissipation.Utilities.Types.Roughness.Neglected 
    "Choice of considering surface roughness";

  extends Utilities.Records.PressureLoss.StraightPipe;

    SI.Length K=0 "Roughness (average height of surface asperities)";

end dp_turbulent_IN_con;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_turbulent_IN_var

Input record for function dp_turbulent_DP and dp_turbulent_MFLOW

Information

This record is used as input record for the pressure loss function dp_turbulent_DP and dp_turbulent_MFLOW.

Extends from Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_var (Input record for function dp_overall_DP and dp_overall_MFLOW).

Parameters

Type Name Default Description

Fluid properties

DynamicViscosity eta Dynamic viscosity of fluid [Pa.s]

Density rho Density of fluid [kg/m3]

Type	Name	Description
Fluid properties
DynamicViscosity	eta	Dynamic viscosity of fluid [Pa.s]
Density	rho	Density of fluid [kg/m3]

Modelica definition

record dp_turbulent_IN_var 
  "Input record for function dp_turbulent_DP and dp_turbulent_MFLOW"

  extends Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_overall_IN_var;

end dp_turbulent_IN_var;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_DP

Pressure loss of straight pipe for two phase flow | calculate (frictional, momentum, geodetic) pressure loss

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_DP

Information

Calculation of pressure loss for two phase flow in a horizontal or vertical straight pipe for an overall flow regime considering frictional, momentum and geodetic pressure loss.

Generally the pressure loss for two phase flow in a horizontal or a vertical straight pipe can be calculated for the following fluid flow regimes:

Horizontal fluid flow [(a) bubble flow, (b) stratified flow, (c) wavy flow, (d) slug flow, (e) annular flow]:

Vertical fluid flow [(a) bubble flow, (b) plug slug flow, (c) foam flow, (d) annular streak flow, (e) annular flow]:

See more information.

Extends from Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d (Geometry figure for straight pipe).

Inputs

Type Name Default Description

Constant inputs

dp_twoPhaseOverall_IN_con IN_con Input record for function dp_twoPhaseOverall_DP

Variable inputs

dp_twoPhaseOverall_IN_var IN_var Input record for function dp_twoPhaseOverall_DP

Input

MassFlowRate m_flow Mass flow rate [kg/s]

Type	Name	Description
Constant inputs
dp_twoPhaseOverall_IN_con	IN_con	Input record for function dp_twoPhaseOverall_DP
Variable inputs
dp_twoPhaseOverall_IN_var	IN_var	Input record for function dp_twoPhaseOverall_DP
Input
MassFlowRate	m_flow	Mass flow rate [kg/s]

Outputs

Type Name Description

Pressure DP Two phase pressure loss [Pa]

Type	Name	Description
Pressure	DP	Two phase pressure loss [Pa]

Modelica definition

function dp_twoPhaseOverall_DP 
  "Pressure loss of straight pipe for two phase flow | calculate (frictional, momentum, geodetic) pressure loss"
  //SOURCE_1: Friedel,L.:IMPROVED FRICTION PRESSURE DROP CORRELATIONS FOR HORIZONTAL AND VERTICAL TWO PHASE PIPE FLOW, 3R International, Vol. 18, Issue 7, pp. 485-491, 1979
  //SOURCE_2: Chisholm,D.:PRESSURE GRADIENTS DUE TO FRICTION DURING THE FLOW OF EVAPORATING TWO-PHASE MIXTURES IN SMOOTH TUBES AND CHANNELS, Int. J. Heat Mass Transfer, Vol. 16, pp. 347-358, Pergamon Press 1973
  //SOURCE_3: VDI-Waermeatlas, 10th edition, Springer-Verlag, 2006.
  //SOURCE 4: J.M. Jensen and H. Tummescheit. Moving boundary models for dynamic simulations of two-phase flows. In Proceedings of the 2nd International Modelica Conference, pp. 235-244, Oberpfaffenhofen, Germany, 2002. The Modelica Association.
  //SOURCE_5: Thome, J.R., Engineering Data Book 3, Swiss Federal Institute of Technology Lausanne (EPFL), 2009.

  //icon
  extends Modelica.Fluid.Dissipation.Utilities.Icons.PressureLoss.StraightPipe_d;

  //input records
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_IN_con
    IN_con "Input record for function dp_twoPhaseOverall_DP";
  input Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_IN_var
    IN_var "Input record for function dp_twoPhaseOverall_DP";
  input SI.MassFlowRate m_flow "Mass flow rate";

  //output variables
  output SI.Pressure DP "Two phase pressure loss";

protected 
  type TYP =
      Modelica.Fluid.Dissipation.Utilities.Types.TwoPhaseFrictionalPressureLoss;

  Real MIN=Modelica.Constants.eps;

  SI.Area A_cross=max(MIN, IN_con.A_cross) "Cross sectional area";
  SI.Diameter d_hyd=max(MIN, 4*A_cross/max(MIN, IN_con.perimeter)) 
    "Hydraulic diameter";

  Real mdot_A=abs(m_flow)/A_cross "Mass flux";
  Real xflowEnd=min(1, max(0, abs(IN_var.x_flow_end))) 
    "Mass flow rate quality at end of length";
  Real xflowSta=min(1, max(0, abs(IN_var.x_flow_sta))) 
    "Mass flow rate quality at start of length";
  Real x_flow=(xflowEnd + xflowSta)/2 "Mean mass flow rate quality over length";

  //SOURCE_5: p.17-1 to 17-5, sec. 17.1 to 17.2: Considering cross sectional void fraction [epsilon=A_g/(A_g+A_l)]
  Real epsilon=
      Modelica.Fluid.Dissipation.Utilities.Functions.PressureLoss.TwoPhase.VoidFraction(
      IN_con.voidFractionApproach,
      true,
      IN_var.rho_g,
      IN_var.rho_l,
      x_flow) "Void fraction";

  //SOURCE_1: Considering frictional pressure loss w.r.t. to correlation of Friedel
  //SOURCE_2: Considering frictional pressrue loss w.r.t. to correlation of Chisholm
  SI.Pressure DP_fric=if IN_con.frictionalPressureLoss == TYP.Friedel then 
      Modelica.Fluid.Dissipation.Utilities.Functions.PressureLoss.TwoPhase.dp_twoPhaseFriedel_DP(
      IN_con,
      IN_var,
      m_flow) else if IN_con.frictionalPressureLoss == TYP.Chisholm then 
      Modelica.Fluid.Dissipation.Utilities.Functions.PressureLoss.TwoPhase.dp_twoPhaseChisholm_DP(
      IN_con,
      IN_var,
      m_flow) else 0 "Frictional pressure loss";

  //SOURCE_3: p.Lba 4, eq. 22: Considering momentum pressure loss assuming heterogeneous approach for two phase flow
  //Evaporation >> positive momentum pressure loss (assumed vice versa at condenstation)
  SI.Pressure DP_mom=if IN_con.momentumPressureLoss then 
      Modelica.Fluid.Dissipation.Utilities.Functions.PressureLoss.TwoPhase.dp_twoPhaseMomentum_DP(
      IN_con.voidFractionApproach,
      IN_con.massFlowRateCorrection,
      IN_con.A_cross,
      IN_con.perimeter,
      IN_var.rho_g,
      IN_var.rho_l,
      IN_var.x_flow_end,
      IN_var.x_flow_sta,
      abs(m_flow)) else 0 "Momentum pressure loss";

  //SOURCE_3: p.Lbb 1, eq. 4: Considering geodetic pressure loss assuming constant void fraction for flow length
  SI.Pressure DP_geo=if IN_con.geodeticPressureLoss then 
      Modelica.Fluid.Dissipation.Utilities.Functions.PressureLoss.TwoPhase.dp_twoPhaseGeodetic_DP(
      IN_con.voidFractionApproach,
      true,
      IN_con.length,
      IN_con.phi,
      IN_var.rho_g,
      IN_var.rho_l,
      IN_var.x_flow) else 0 "Geodetic pressure loss";

  //Documentation
algorithm 
  DP := DP_fric + DP_mom + DP_geo;

end dp_twoPhaseOverall_DP;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_IN_con

Input record for function dp_twoPhaseOverall_DP

Information

This record is used as input record for the pressure loss function dp_twoPhaseOverall_DP.

Extends from Modelica.Fluid.Dissipation.Utilities.Records.General.TwoPhaseFlow_con (Base record for two phase Flow).

Parameters

Type Name Default Description

Choices

TwoPhaseFrictionalPressureLoss frictionalPressureLoss Dissipation.Utilities.Types.... Choice of frictional pressure loss approach

Roughness voidFractionApproach Dissipation.Utilities.Types.... Choice of void fraction approach

Boolean momentumPressureLoss false Considering momentum pressure loss

Boolean massFlowRateCorrection false Consider heterogeneous mass flow rate correction

Boolean geodeticPressureLoss false Considering geodetic pressure loss

Geometry

Area A_cross PI*0.1^2/4 Cross sectional area [m2]

Length perimeter PI*0.1 Wettet perimeter [m]

Length length 1 Length in fluid flow direction [m]

Angle phi 0 Tilt angle to horizontal [rad]

Type	Name	Default	Description
Choices
TwoPhaseFrictionalPressureLoss	frictionalPressureLoss	Dissipation.Utilities.Types....	Choice of frictional pressure loss approach
Roughness	voidFractionApproach	Dissipation.Utilities.Types....	Choice of void fraction approach
Boolean	momentumPressureLoss	false	Considering momentum pressure loss
Boolean	massFlowRateCorrection	false	Consider heterogeneous mass flow rate correction
Boolean	geodeticPressureLoss	false	Considering geodetic pressure loss
Geometry
Area	A_cross	PI*0.1^2/4	Cross sectional area [m2]
Length	perimeter	PI*0.1	Wettet perimeter [m]
Length	length	1	Length in fluid flow direction [m]
Angle	phi	0	Tilt angle to horizontal [rad]

Modelica definition

record dp_twoPhaseOverall_IN_con 
  "Input record for function dp_twoPhaseOverall_DP"

  //choices
  Modelica.Fluid.Dissipation.Utilities.Types.TwoPhaseFrictionalPressureLoss
    frictionalPressureLoss=Dissipation.Utilities.Types.TwoPhaseFrictionalPressureLoss.Friedel 
    "Choice of frictional pressure loss approach";
  Modelica.Fluid.Dissipation.Utilities.Types.Roughness
    voidFractionApproach =                                                  Dissipation.Utilities.Types.VoidFractionApproach.Homogeneous 
    "Choice of void fraction approach";

  Boolean momentumPressureLoss=false "Considering momentum pressure loss";
  Boolean massFlowRateCorrection=false 
    "Consider heterogeneous mass flow rate correction";
  Boolean geodeticPressureLoss=false "Considering geodetic pressure loss";

  extends Modelica.Fluid.Dissipation.Utilities.Records.General.TwoPhaseFlow_con;
  SI.Angle phi=0 "Tilt angle to horizontal";


end dp_twoPhaseOverall_IN_con;

Modelica.Fluid.Dissipation.PressureLoss.StraightPipe.dp_twoPhaseOverall_IN_var

Input record for function dp_twoPhaseOverall_DP

Information

This record is used as input record for the pressure loss function dp_twoPhaseOverall_DP.

Extends from Modelica.Fluid.Dissipation.Utilities.Records.General.TwoPhaseFlow_var (Base record for two phase flow).

Parameters

Type Name Default Description

Fluid properties

Real x_flow_end 0 Mass flow rate quality at end of length

Real x_flow_sta 0 Mass flow rate quality at start of length

Density rho_g Density of gas [kg/m3]

Density rho_l Density of liquid [kg/m3]

DynamicViscosity eta_g Dynamic viscosity of gas [Pa.s]

DynamicViscosity eta_l Dynamic viscosity of liquid [Pa.s]

SurfaceTension sigma Surface tension [N/m]

Input

Real x_flow (x_flow_end + x_flow_sta)/2 Mean mass flow rate quality over length

Type	Name	Default	Description
Fluid properties
Real	x_flow_end	0	Mass flow rate quality at end of length
Real	x_flow_sta	0	Mass flow rate quality at start of length
Density	rho_g		Density of gas [kg/m3]
Density	rho_l		Density of liquid [kg/m3]
DynamicViscosity	eta_g		Dynamic viscosity of gas [Pa.s]
DynamicViscosity	eta_l		Dynamic viscosity of liquid [Pa.s]
SurfaceTension	sigma		Surface tension [N/m]
Input
Real	x_flow	(x_flow_end + x_flow_sta)/2	Mean mass flow rate quality over length

Modelica definition

record dp_twoPhaseOverall_IN_var 
  "Input record for function dp_twoPhaseOverall_DP"

  Real x_flow_end=0 "Mass flow rate quality at end of length";
  Real x_flow_sta=0 "Mass flow rate quality at start of length";
  extends Modelica.Fluid.Dissipation.Utilities.Records.General.TwoPhaseFlow_var
    (                                                                           final 
      x_flow=(x_flow_end + x_flow_sta)/2);


end dp_twoPhaseOverall_IN_var;

Automatically generated Fri Nov 12 16:31:22 2010.